1. Field of the Invention
This invention relates generally to aerators, and more particularly to a variable venturi sewerage aerator.
2. Prior Art
The use of varied designed aerators in a multitude of industries is well known. However, sewerage treatment presents many special problems that can not be as effectively or as efficiently handled by present art techniques such as those disclosed in the following illustrated U.S. patents:
______________________________________ U.S. PAT. NO. INVENTOR ISSUED TITLE ______________________________________ Re 22,654 1,774,793 Egan 4/9/27 "SEWER CONSTRUCTION" 2,374,772 Nordell 5/1/45 "APPARATUS FOR AERATING SEWAGE" 3,517,812 D. Bucchioni 6/30/70 "PROCESS AND APPARATUS FOR RE- MOVING FLOATING WASTE FROM WATER SURFACES" 3,701,429 Schell 10/31/72 "SKIMMER FOR RE- MOVING FLOATING MATTER FROM A BODY OF LIQUID" 3,744,257 Spanner 7/10/73 "WATER-SURFACE CLEANSING SHIP" 4,038,185 Kline 7/26/77 "SCUM CONTROL SYSTEM FOR PERIPHERAL FEED CHANNEL OF SEDI- MENTATION TANK 4,087,361 Block, et al 5/2/78 "ACTIVATED SLUDGE SYSTEM WITH STAGGERED PARTITION BASIN" 4,116,835 Bertelson 9/26/78 "POLLUTION CONTROL SYSTEM" 4,119,541 Makaya 10/10/78 "ARRANGEMENT FOR DISPOSING OF FLUID FLOATING MATTER" 4,219,424 Tamura et al 8/26/80 "APPARATUS FOR ENRICHING OXYGEN CONTAINED IN WATER" ______________________________________
Some of the main difficulties include equipment clogging due to the nature of the liquid sewerage, difficulty in repairing clogged equipment due to its submerged location, restrictions on the amount of air supplied to sewerage per pump horsepower needed, insufficient sewerage exposure to air due to large air bubble size, too limited exposure time between the sewerage and the air, inability to rapidly vary air flow rates to compensate for changes in sewerage composition, and inability of equipment to handle a variety of wastewater treatment applications.
The best available equipment includes design such as that sold by Hondaille Industries, Inc. as shown in their advertising brochures PAATB979-10M. However, such equipment still retains many of the above mentioned problems.